This invention relates to panel type display apparatus which make use of gas discharge for the display of such information as characters and drawings by selectively controlling the discharge of a number of display element sections.
The panel type display apparatus, which is well known as a character display of gas discharge type, has a construction in which a number of display element sections are provided at intersections of pluralities of cathodes and anodes extending perpendicular to one another. When one or more of the cathodes and anodes are selected, corresponding intersections are specified. A high voltage is applied between the cathode and anode at the specified intersections, whereby gas discharge is caused at these intersections to cause generation of dots of light therefrom. Predetermined characters or drawings are displayed as corresponding combinations of such light dots.
The panel type display apparatus of this kind has a construction comprising a transparent front plate and a back plate facing and defining a narrow space with the front plate, with a discharge gas sealed in the narrow space. A number of parallel strip-like cathodes are provided on the inner surface of the back plate. A lattice-shaped insulating rib structure is provided to divide the cathodes and define a plurality of display element sections. Anodes are provided on the inner surface of the front plate along portions thereof corresponding to the insulating rib structure such that intersections of cathode and anode are provided for the individual display element sections mentioned above.
More particularly, a number of cathodes are formed on the back plate and a number of anodes on the front plate using printing techniques. Also, the insulating rib structure which defines a number of display element sections is formed on the back plate or on the front plate or formed as divisions on both the plates. The panel type display apparatus is obtained by assembling the back and front plate such that these plates correctly face each other.
In the display apparatus of this construction, therefore, the cathodes, anodes and insulating rib structure have to be formed on the back and front plates with sufficiently high precision. Also, a display apparatus which has a predetermined display function cannot be obtained unless the back and front plates are assembled together with high precision.
With the above display apparatus, for which very high precision is required in its manufacture, therefore, it is difficult to improve the yield. Further, it is difficult to reduce the area of the individual display element sections for reducing the display elements and improve the density of display.